Improved furnace for roasting ores



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E. P. HUDSON.

Roasting Gres. No. 78,456. A PatemedJune 2,1358.

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Patented .lune 2, i868f roven/ZU? 'UNITED STATES PATEITWQgEloE.

EDNARD P. HUDSON, OF NEW YORK, N. Y.

IMPROVED FURNACE FOR ROASTING ORES.

Specification forming part of Letters Patent No. 73,456, dated June 2,1868.

To all 'whom it may concern:

Be it known that I, EDWARD P. HUDsoN, of New York, in the county andState of New York, have invented an Improved Furnace and ResultingProcess for Roasting and Dcsulphurizing Ores; and I do hereby declarethat the following is a full and exact description thereof, referencebeing had to the accompanying drawings, making part of thisspecification- Figure l being a central vertical sect-ion of the furnacethrough the fire-chambers 5 Fig.'2,

sa horizontal section'thereof in a plane indicated by the line Fig. 1;Fig. 3, a vertical section, corresponding with Fig. 1, of a modifiedform of the furnace.

Like letters designate corresponding parts in all of the gures. Theobject of my invention is to thoroughly remove sulphur, phosphorus,arsenic, and other noxious substances from ores with economy, so thatores containing such ingredients, after treatment by my improvedprocess, may be successfully reduced to their metallic bases in a purestate.

Three important results are attained by the construction of thisfurnace: First, ahigh degree of heat is secured, with economy in fuel,second, an excess of oxygen, the desulphurizing agent, is presented toall parts of the mass of ore without detractin g from the temperature;third, the ore, when sufficiently treated, is readily removed from thefurnace without obstructing the continuous operations in the treatmentof succeeding charges of ores.

Let A represent the interior or ore-treating chamber; B C, theDre-chambers, and D the hearth of the furnace. The width ofthe chamberA, between the fire-chambers, should not be so great as not to allow acomplete circulation of the heated air into the center of the mass ofthe ore.

First, the fire-chamber B, on one side, is located just above the upperedge of the inclined hearth D, opposite to the side where the treatedore is drawn out at the door g,- and the fire-chamber C, on the oppositeside, is located at a higher level than the chamber B, so as to givesufficient room below for taking out the ores, and in order to moreeasily and effectuall y distribute the heat and air of the blast to theore. The arrangement is substantially represented in Fig. l.

Second, the hearth D is inclined from below the lower Vhre-chamber, B,downward to the door g, where the ore is drawn out after treatment. Thisinclination of the hearth from one side to the other enables the treatedores, as they settle to the bottom, to be removed quite equally from themiddle and both sides. It

also furnishes a chamber or reservoir, a, at the bottom of the mainore-chamber A, into which the ore, as it becomes completelydesulphurized or treated, settles below the furnaces, wherein it canpartially cool before being removed.

Instead of the singly-inclined hearth and fire-chambers at differentheights, as shown in Fig. l, an arrangement indicated in Fig. 3 may beadopted. Here the hearth inclines both ways to two doors, g g, forremoving the ore, and both fire-chambers, B C, are at the same height,at least entirely above the highest part of the hearth D, so that achamber or chambers is furnished below the irecham bers, as in thefirst-described arrangement.

Third, air is introduced into the orecham ber through the hearth D, ornear the same, at

the side or sides of the furnace, or at least below the fire-chambers,by a pipe or pipes, 7L, so that it is heated by the cooling ore on thehearth, whereby, in turn, the ore is assisted in cooling. Thus, also,the air is introduced in to the ore undergoing treatment without rstpassing through the fuel, which would deprive the air of its oxygen, andthus prevent its becoming a desulphurizing agent, and thereby act in themost efficient manner for desulphurA izing the ore at the moment ofbeing decomposed.

Fourth, besides the introduction of air as a desulphurizin g agentthrough the desulphurized ores in the cooling chamber or reservoir,atmospheric air is introduced into the ore through the fire-chambers BC, cach of which has one' or more pipes or passages, d, extend ing fromthe air-chamber b, below the tiregrate, into the space c above the fuel,through which the air is conducted in excess above the re without beingdecomposed in the fuel, and is thence forced, in a heated state, intothe mass of ore by the pressure from the blastpipe f, which leads intothe air-chamber below the fire. Y'

The pipe or passage d is controlled by a valve, so as to regulate theamount of free air thus admitted into the furnace, or cut it oientirely; and the air passage or pipe or passages h is also providedWith a Valve to regulate or eut ott the low of air into the furnacethrough or at the hearth. Thus free air may be introduced into the oreeither at the bottom or above the lire chamber or chambers, or throughboth, or both may be cut off, as when first heating a charge of ore fortreatment, or the amount and relative proportion of air at the differentinlets may be regulated. This regulated-variation of the introduction ofair 1s desirable, if not necessary, to the proper treatment of differentkinds or qualities of ores, as Well as in different stages of theprocess of desulphurization.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. Forcing heated air or oxygen, in addition to the products ofcombustion, through ores,

`tires, so as to be heated thereby before passing through the ores,substantially as herein specified.

4. The arrangement of one tire-chamber higher than the other,substantially as and for the purpose herein specified.

EDWARD P. HUDSON.

Witnesses;

SE'rH ALLEN, F. A. ALLEN.

